#include <zephyr/fs/littlefs.h>
#include <zephyr/fs/fs.h>
#include <zephyr/sys/byteorder.h>
#include <zephyr/logging/log.h>
#include <zephyr/pm/device.h>
#include <zephyr/sys/crc.h>

#include "fs_mgmt.h"
#include "buzz_proto.h"

LOG_MODULE_REGISTER(fs_mgmt, CONFIG_FS_MGMT_LOG_LEVEL);

#define FS_PARTITION_ID FLASH_AREA_ID(littlefs_storage)
FS_LITTLEFS_DECLARE_DEFAULT_CONFIG(fs_storage_data);

#define QSPI_FLASH_NODE DT_ALIAS(qspi_flash)
static const struct device *flash_dev = DEVICE_DT_GET(QSPI_FLASH_NODE);

#define TAG_MAGIC "TAG!"
#define TAG_FORMAT_VERSION 1U

static struct fs_mount_t fs_storage_mnt = {
    .type = FS_LITTLEFS,
    .fs_data = &fs_storage_data,
    .storage_dev = (void *)FS_PARTITION_ID,
    .mnt_point = CONFIG_FS_MGMT_MOUNT_POINT,
};

static int open_count = 0;
static struct k_mutex flash_pm_lock;

#define ACK_WATERMARK (CONFIG_BUZZ_PROTO_SLAB_COUNT / 4)

typedef struct __attribute__((packed))
{
    uint16_t total_size;
    uint16_t version;
    uint8_t magic[4];
} tag_footer_t;

K_MSGQ_DEFINE(fs_write_msgq, sizeof(struct fs_write_msg), CONFIG_BUZZ_PROTO_SLAB_COUNT, 4);

typedef enum {
    FS_STATE_IDLE,
    FS_STATE_RECEIVING_FILE,
    FS_STATE_RECEIVING_TAGS,
    FS_STATE_RECEIVING_FIRMWARE
} fs_thread_state_t;

static struct
{
    fs_thread_state_t state;
    struct fs_file_t file;
    char filename[FS_MGMT_MAX_PATH_LENGTH];
    uint32_t crc32;
    uint16_t unacked_chunks;
    off_t audio_len; // Offeset für Tags
} write_ctx;

/**
 * @brief Puts the QSPI flash into deep sleep mode to save power
 *       Decrements the open count and suspends the flash if no more users are active
 * @return 0 on success, negative error code on failure
 */
static int fs_mgmt_pm_flash_suspend(void)
{
#if IS_ENABLED(CONFIG_PM_DEVICE)
    if (!device_is_ready(flash_dev))
    {
        return -ENODEV;
    }

    k_mutex_lock(&flash_pm_lock, K_FOREVER);

    if (open_count > 0)
    {
        open_count--;
        if (open_count == 0)
        {
            int rc = pm_device_action_run(flash_dev, PM_DEVICE_ACTION_SUSPEND);
            if (rc < 0)
            {
                LOG_WRN("Could not suspend flash: %d", rc);
            }
            else
            {
                LOG_DBG("Flash entered deep power-down");
            }
        }
    }

    k_mutex_unlock(&flash_pm_lock);
#endif /* CONFIG_PM_DEVICE */
    return 0;
}

/**
 * @brief Resumes the QSPI flash from deep sleep mode
 *       Increments the open count and resumes the flash if it was previously suspended
 * @return 0 on success, negative error code on failure
 */
static int fs_mgmt_pm_flash_resume(void)
{
#if IS_ENABLED(CONFIG_PM_DEVICE)
    if (!device_is_ready(flash_dev))
        return -ENODEV;

    k_mutex_lock(&flash_pm_lock, K_FOREVER);

    if (open_count == 0)
    {
        int rc = pm_device_action_run(flash_dev, PM_DEVICE_ACTION_RESUME);
        if (rc == 0)
        {
            k_busy_wait(50); // t-exit-dpd
            LOG_DBG("Flash resumed");
        }
    }
    open_count++;

    k_mutex_unlock(&flash_pm_lock);
#endif /* CONFIG_PM_DEVICE */
    return 0;
}

int fs_mgmt_pm_open(struct fs_file_t *file, const char *path, fs_mode_t mode)
{
    LOG_DBG("PM Opening file '%s' with mode 0x%02x", path, mode);
    fs_mgmt_pm_flash_resume();
    int rc = fs_open(file, path, mode);
    if (rc < 0)
    {
        fs_mgmt_pm_flash_suspend();
    }
    return rc;
}

int fs_mgmt_pm_close(struct fs_file_t *file)
{
    LOG_DBG("PM Closing file");
    int rc = fs_close(file);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_opendir(struct fs_dir_t *dirp, const char *path)
{
    LOG_DBG("PM Opening directory '%s'", path);
    fs_mgmt_pm_flash_resume();
    int rc = fs_opendir(dirp, path);
    if (rc < 0)
    {
        fs_mgmt_pm_flash_suspend();
    }
    return rc;
}

int fs_mgmt_pm_closedir(struct fs_dir_t *dirp)
{
    LOG_DBG("PM Closing directory");
    int rc = fs_closedir(dirp);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_unlink(const char *path)
{
    LOG_DBG("PM Unlinking file '%s'", path);
    fs_mgmt_pm_flash_resume();
    int rc = fs_unlink(path);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_statvfs(const char *path, struct fs_statvfs *stat)
{
    LOG_DBG("PM Getting filesystem stats for '%s'", path);
    fs_mgmt_pm_flash_resume();
    int rc = fs_statvfs(path, stat);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_stat(const char *path, struct fs_dirent *entry)
{
    LOG_DBG("PM Getting stat for '%s'", path);
    fs_mgmt_pm_flash_resume();
    int rc = fs_stat(path, entry);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_mkdir(const char *path)
{
    LOG_DBG("PM Creating directory '%s'", path);
    fs_mgmt_pm_flash_resume();
    int rc = fs_mkdir(path);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_rename(const char *old_path, const char *new_path)
{
    LOG_DBG("PM Renaming '%s' to '%s'", old_path, new_path);
    fs_mgmt_pm_flash_resume();
    int rc = fs_rename(old_path, new_path);
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_rm_recursive(char *path_buf, size_t max_len)
{
    struct fs_dirent entry;
    struct fs_dir_t dir;
    int rc;

    fs_mgmt_pm_flash_resume();

    /* 1. Stat prüfen: Ist es eine Datei? */
    rc = fs_stat(path_buf, &entry);
    if (rc != 0)
    {
        fs_mgmt_pm_flash_suspend();
        return rc;
    }

    /* Wenn es eine Datei ist, direkt löschen und beenden */
    if (entry.type == FS_DIR_ENTRY_FILE)
    {
        rc = fs_unlink(path_buf);
        fs_mgmt_pm_flash_suspend();
        return rc;
    }

    /* 2. Es ist ein Verzeichnis. Schleife bis es leer ist. */
    size_t orig_len = strlen(path_buf);

    while (1)
    {
        fs_dir_t_init(&dir);
        rc = fs_opendir(&dir, path_buf);
        if (rc != 0)
        {
            break;
        }

        bool found_something = false;

        /* Genau EINEN löschbaren Eintrag suchen */
        while (1)
        {
            rc = fs_readdir(&dir, &entry);
            if (rc != 0 || entry.name[0] == '\0')
            {
                break; /* Ende oder Fehler */
            }
            if (strcmp(entry.name, ".") == 0 || strcmp(entry.name, "..") == 0)
            {
                continue; /* Ignorieren */
            }

            found_something = true;
            break; /* Treffer! Schleife abbrechen. */
        }

        /* WICHTIG: Das Verzeichnis SOFORT schließen, BEVOR wir rekurieren!
         * Damit geben wir das File-Handle (NUM_DIRS) an Zephyr zurück. */
        fs_closedir(&dir);

        if (!found_something || rc != 0)
        {
            break; /* Verzeichnis ist nun restlos leer */
        }

        size_t name_len = strlen(entry.name);
        if (orig_len + 1 + name_len >= max_len)
        {
            rc = -ENAMETOOLONG;
            break;
        }

        /* Pfad für das gefundene Kindelement bauen */
        path_buf[orig_len] = '/';
        strcpy(&path_buf[orig_len + 1], entry.name);

        /* Rekursiver Aufruf für das Kind */
        rc = fs_mgmt_pm_rm_recursive(path_buf, max_len);

        /* Puffer sofort wieder auf unser Verzeichnis zurückschneiden */
        path_buf[orig_len] = '\0';

        if (rc != 0)
        {
            break; /* Abbruch, falls beim Löschen des Kindes ein Fehler auftrat */
        }
    }

    /* 3. Das nun restlos leere Verzeichnis selbst löschen */
    if (rc == 0)
    {
        rc = fs_unlink(path_buf);
    }

    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_pm_mkdir_recursive(char *path)
{
    int rc = 0;
    struct fs_dirent entry;
    char *p = path;

    /* Führenden Slash überspringen, falls vorhanden (z. B. bei "/lfs") */
    if (*p == '/')
    {
        p++;
    }

    /* Flash für den gesamten Durchlauf aktivieren */
    fs_mgmt_pm_flash_resume();

    while (*p != '\0')
    {
        if (*p == '/')
        {
            *p = '\0'; /* String temporär am aktuellen Slash terminieren */

            /* Prüfen, ob dieser Pfadabschnitt bereits existiert */
            rc = fs_stat(path, &entry);

            if (rc == -ENOENT)
            {
                /* Existiert nicht -> anlegen */
                rc = fs_mkdir(path);
                if (rc != 0)
                {
                    *p = '/'; /* Bei Fehler Slash wiederherstellen und abbrechen */
                    break;
                }
            }
            else if (rc == 0)
            {
                /* Existiert -> prüfen, ob es ein Verzeichnis ist */
                if (entry.type != FS_DIR_ENTRY_DIR)
                {
                    rc = -ENOTDIR;
                    *p = '/';
                    break;
                }
            }
            else
            {
                /* Anderer Dateisystemfehler */
                *p = '/';
                break;
            }

            *p = '/'; /* Slash für den nächsten Schleifendurchlauf wiederherstellen */
        }
        p++;
    }

    /* Letztes Element verarbeiten, falls der Pfad nicht mit '/' endet */
    if (rc == 0 && p > path && *(p - 1) != '/')
    {
        rc = fs_stat(path, &entry);
        if (rc == -ENOENT)
        {
            rc = fs_mkdir(path);
        }
        else if (rc == 0)
        {
            if (entry.type != FS_DIR_ENTRY_DIR)
            {
                rc = -ENOTDIR;
            }
        }
    }

    /* Flash am Ende wieder in den Suspend schicken */
    fs_mgmt_pm_flash_suspend();
    return rc;
}

int fs_mgmt_init(void)
{
    k_mutex_init(&flash_pm_lock);

    if (!device_is_ready(flash_dev))
    {
        LOG_ERR("Flash device not ready!");
        return -ENODEV;
    }

    fs_mgmt_pm_flash_resume();

    int rc = fs_mount(&fs_storage_mnt);

    if (rc < 0)
    {
        LOG_ERR("Error mounting filesystem: %d", rc);
        return rc;
    }
    fs_mgmt_pm_flash_suspend();
    LOG_DBG("Filesystem mounted successfully");
    return 0;
}

static int fs_get_tag_bounds(struct fs_file_t *fp, off_t file_size,
                             size_t *audio_limit, size_t *payload_len, bool *has_tag)
{
    tag_footer_t footer;

    if (audio_limit == NULL || payload_len == NULL || has_tag == NULL)
    {
        return -EINVAL;
    }

    *has_tag = false;
    *audio_limit = (size_t)file_size;
    *payload_len = 0U;

    if (file_size < (off_t)sizeof(tag_footer_t))
    {
        return 0;
    }

    fs_seek(fp, -(off_t)sizeof(tag_footer_t), FS_SEEK_END);
    if (fs_read(fp, &footer, sizeof(tag_footer_t)) != sizeof(tag_footer_t))
    {
        fs_seek(fp, 0, FS_SEEK_SET);
        return -EIO;
    }

    if (memcmp(footer.magic, TAG_MAGIC, 4) != 0)
    {
        fs_seek(fp, 0, FS_SEEK_SET);
        return 0;
    }

    uint16_t tag_version = sys_le16_to_cpu(footer.version);
    uint16_t tag_len = sys_le16_to_cpu(footer.total_size);

    if (tag_version != TAG_FORMAT_VERSION)
    {
        fs_seek(fp, 0, FS_SEEK_SET);
        return -ENOTSUP;
    }

    if (tag_len > (uint16_t)file_size || tag_len < sizeof(tag_footer_t))
    {
        fs_seek(fp, 0, FS_SEEK_SET);
        return -EBADMSG;
    }

    *has_tag = true;
    *audio_limit = (size_t)file_size - tag_len;
    *payload_len = tag_len - sizeof(tag_footer_t);

    fs_seek(fp, 0, FS_SEEK_SET);
    return 0;
}

ssize_t fs_get_audio_data_len(struct fs_file_t *fp)
{
    off_t file_size;
    size_t audio_limit = 0U;
    size_t payload_len = 0U;
    bool has_tag = false;

    fs_seek(fp, 0, FS_SEEK_END);
    file_size = fs_tell(fp);

    if (file_size < 0)
    {
        fs_seek(fp, 0, FS_SEEK_SET);
        return -EIO;
    }

    if (fs_get_tag_bounds(fp, file_size, &audio_limit, &payload_len, &has_tag) < 0)
    {
        fs_seek(fp, 0, FS_SEEK_SET);
        return -EIO;
    }

    fs_seek(fp, 0, FS_SEEK_SET);
    return has_tag ? (ssize_t)audio_limit : file_size;
}

int fs_mgmt_submit_write(struct fs_write_msg *msg)
{
    return k_msgq_put(&fs_write_msgq, msg, K_NO_WAIT);
}

static void fs_thread_entry(void *p1, void *p2, void *p3)
{
    LOG_INF("FS Write Thread started");
    write_ctx.state = FS_STATE_IDLE;
    fs_file_t_init(&write_ctx.file);
    struct fs_write_msg msg;

    while (1)
    {
        /* Watchdog nur bei aktiven Transfers */
        k_timeout_t wait_time = (write_ctx.state == FS_STATE_IDLE) ? K_FOREVER : K_SECONDS(2);
        int rc = k_msgq_get(&fs_write_msgq, &msg, wait_time);

        if (rc == -EAGAIN)
        {
            LOG_WRN("Write timeout! Aborting transfer.");
            if (write_ctx.state == FS_STATE_RECEIVING_FILE) {
                fs_mgmt_pm_close(&write_ctx.file);
                fs_mgmt_pm_unlink(write_ctx.filename);
            }
            write_ctx.state = FS_STATE_IDLE;
            continue;
        }

        switch (write_ctx.state)
        {
        case FS_STATE_IDLE:
            if (msg.op == FS_WRITE_OP_FILE_START)
            {
                if (msg.data_len >= sizeof(write_ctx.filename)) {
                    LOG_ERR("Filename too long");
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, ENAMETOOLONG, msg.slab_ptr);
                    break;
                }
                
                memcpy(write_ctx.filename, msg.slab_ptr + msg.data_offset, msg.data_len);
                write_ctx.filename[msg.data_len] = '\0';
                
                fs_mgmt_pm_unlink(write_ctx.filename); 
                rc = fs_mgmt_pm_open(&write_ctx.file, write_ctx.filename, FS_O_CREATE | FS_O_WRITE);
                
                if (rc == 0) {
                    write_ctx.state = FS_STATE_RECEIVING_FILE;
                    write_ctx.crc32 = 0;
                    write_ctx.unacked_chunks = 0;
                    LOG_INF("File transfer started: %s (Expected: %u bytes)", write_ctx.filename, msg.metadata);
                    
                    uint16_t credits = buzz_proto_get_free_rx_slabs();
                    buzz_proto_buf_free(&msg.slab_ptr);
                    buzz_proto_send_ack(msg.reply_cb, credits);
                } else {
                    LOG_ERR("Failed to open %s: %d", write_ctx.filename, rc);
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, abs(rc), msg.slab_ptr);
                }
            }/* Innerhalb von case FS_STATE_IDLE: */
            else if (msg.op == FS_WRITE_OP_TAGS_START)
            {
                if (msg.data_len >= sizeof(write_ctx.filename)) {
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, ENAMETOOLONG, msg.slab_ptr);
                    break;
                }
                
                memcpy(write_ctx.filename, msg.slab_ptr + msg.data_offset, msg.data_len);
                write_ctx.filename[msg.data_len] = '\0';
                
                /* Datei öffnen: Nur Lese- und Schreibrechte, Datei muss bereits existieren */
                int rc = fs_mgmt_pm_open(&write_ctx.file, write_ctx.filename, FS_O_READ | FS_O_WRITE);
                
                if (rc == 0) {
                    ssize_t audio_len = fs_get_audio_data_len(&write_ctx.file);
                    
                    if (audio_len < 0) {
                        LOG_ERR("Failed to get audio length: %d", (int)audio_len);
                        fs_mgmt_pm_close(&write_ctx.file);
                        buzz_proto_send_error_reusing_slab(msg.reply_cb, EIO, msg.slab_ptr);
                        break;
                    }

                    /* Datei ab dem Ende der Audiodaten abschneiden (alte Tags entfernen) */
                    rc = fs_truncate(&write_ctx.file, audio_len);
                    if (rc != 0) {
                        LOG_ERR("Failed to truncate file: %d", rc);
                        fs_mgmt_pm_close(&write_ctx.file);
                        buzz_proto_send_error_reusing_slab(msg.reply_cb, abs(rc), msg.slab_ptr);
                        break;
                    }

                    /* File-Pointer exakt an das neue Ende (audio_len) setzen */
                    fs_seek(&write_ctx.file, audio_len, FS_SEEK_SET);

                    write_ctx.state = FS_STATE_RECEIVING_TAGS;
                    write_ctx.crc32 = 0;
                    write_ctx.unacked_chunks = 0;
                    write_ctx.audio_len = audio_len;
                    
                    LOG_INF("Tags transfer started: %s (Expected tags: %u bytes)", write_ctx.filename, msg.metadata);
                    
                    uint16_t credits = buzz_proto_get_free_rx_slabs();
                    buzz_proto_buf_free(&msg.slab_ptr);
                    buzz_proto_send_ack(msg.reply_cb, credits);
                } else {
                    LOG_ERR("Failed to open %s for tags: %d", write_ctx.filename, rc);
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, abs(rc), msg.slab_ptr);
                }
            }            else if ( msg.op == FS_WRITE_OP_FW_START) 
            {
                LOG_WRN("Operation not yet fully implemented in FS state machine");
                buzz_proto_send_error_reusing_slab(msg.reply_cb, ENOSYS, msg.slab_ptr);
            }
            break;

        case FS_STATE_RECEIVING_FILE:
            if (msg.op == FS_WRITE_OP_FILE_CHUNK && msg.slab_ptr)
            {
                ssize_t written = fs_write(&write_ctx.file, msg.slab_ptr + msg.data_offset, msg.data_len);
                
                if (written == msg.data_len) {
                    write_ctx.crc32 = crc32_ieee_update(write_ctx.crc32, msg.slab_ptr + msg.data_offset, msg.data_len);
                    buzz_proto_buf_free(&msg.slab_ptr);
                    write_ctx.unacked_chunks++;
                    if (write_ctx.unacked_chunks >= ACK_WATERMARK) {
                        uint16_t free_slabs = buzz_proto_get_free_rx_slabs();
                        uint16_t credits_to_send = MIN(free_slabs, write_ctx.unacked_chunks);
                        if (credits_to_send > 0) {
                            buzz_proto_send_ack(msg.reply_cb, credits_to_send);
                            write_ctx.unacked_chunks -= credits_to_send;
                        }                        
                    }
                } else {
                    LOG_ERR("Flash write failed!");
                    write_ctx.state = FS_STATE_IDLE;
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, EIO, msg.slab_ptr);
                }
            }
            else if (msg.op == FS_WRITE_OP_FILE_END)
            {
                fs_mgmt_pm_close(&write_ctx.file);
                write_ctx.state = FS_STATE_IDLE;
                
                if (write_ctx.crc32 == msg.metadata) {
                    LOG_INF("File transfer finished. CRC valid: 0x%08X", write_ctx.crc32);
                    buzz_proto_send_success_reusing_slab(msg.reply_cb, BUZZ_DATA_FILE_PUT, msg.slab_ptr);
                } else {
                    LOG_ERR("CRC Mismatch! Expected: 0x%08X, Got: 0x%08X", msg.metadata, write_ctx.crc32);
                    fs_mgmt_pm_unlink(write_ctx.filename);
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, EBADMSG, msg.slab_ptr);
                }
            }
            else if (msg.op == FS_WRITE_OP_ABORT)
            {
                fs_mgmt_pm_close(&write_ctx.file);
                fs_mgmt_pm_unlink(write_ctx.filename);
                write_ctx.state = FS_STATE_IDLE;
                if (msg.slab_ptr) buzz_proto_buf_free(&msg.slab_ptr);
            }
            break;
            
            case FS_STATE_RECEIVING_TAGS:
            if (msg.op == FS_WRITE_OP_FILE_CHUNK && msg.slab_ptr)
            {
                ssize_t written = fs_write(&write_ctx.file, msg.slab_ptr + msg.data_offset, msg.data_len);
                
                if (written == msg.data_len) {
                    write_ctx.crc32 = crc32_ieee_update(write_ctx.crc32, msg.slab_ptr + msg.data_offset, msg.data_len);
                    buzz_proto_buf_free(&msg.slab_ptr);
                    
                    write_ctx.unacked_chunks++;
                    if (write_ctx.unacked_chunks >= ACK_WATERMARK) {
                        uint16_t free_slabs = buzz_proto_get_free_rx_slabs();
                        uint16_t credits_to_send = MIN(free_slabs, write_ctx.unacked_chunks);
                        if (credits_to_send > 0) {
                            buzz_proto_send_ack(msg.reply_cb, credits_to_send);
                            write_ctx.unacked_chunks -= credits_to_send;
                        }                        
                    }
                } else {
                    LOG_ERR("Flash write failed during tags transfer!");
                    fs_truncate(&write_ctx.file, write_ctx.audio_len); /* Rollback */
                    fs_mgmt_pm_close(&write_ctx.file);
                    write_ctx.state = FS_STATE_IDLE;
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, EIO, msg.slab_ptr);
                }
            }
            else if (msg.op == FS_WRITE_OP_FILE_END)
            {
                if (write_ctx.crc32 == msg.metadata) {
                    LOG_INF("Tags transfer finished. CRC valid: 0x%08X", write_ctx.crc32);
                    fs_mgmt_pm_close(&write_ctx.file);
                    buzz_proto_send_success_reusing_slab(msg.reply_cb, BUZZ_DATA_TAGS_PUT, msg.slab_ptr);
                } else {
                    LOG_ERR("Tags CRC Mismatch! Expected: 0x%08X, Got: 0x%08X", msg.metadata, write_ctx.crc32);
                    fs_truncate(&write_ctx.file, write_ctx.audio_len); /* Rollback */
                    fs_mgmt_pm_close(&write_ctx.file);
                    buzz_proto_send_error_reusing_slab(msg.reply_cb, EBADMSG, msg.slab_ptr);
                }
                write_ctx.state = FS_STATE_IDLE;
            }
            else if (msg.op == FS_WRITE_OP_ABORT)
            {
                fs_truncate(&write_ctx.file, write_ctx.audio_len); /* Rollback */
                fs_mgmt_pm_close(&write_ctx.file);
                write_ctx.state = FS_STATE_IDLE;
                if (msg.slab_ptr) buzz_proto_buf_free(&msg.slab_ptr);
            }
            break;
            
        case FS_STATE_RECEIVING_FIRMWARE:
            break;
        }

        /* Garbage Collection: Ungültige Operationen im falschen State abfangen */
        if (write_ctx.state == FS_STATE_IDLE && msg.op == FS_WRITE_OP_FILE_CHUNK && msg.slab_ptr) {
            buzz_proto_buf_free(&msg.slab_ptr);
        }
    }
}

K_THREAD_DEFINE(fs_thread, CONFIG_FS_MGMT_THREAD_STACK_SIZE, fs_thread_entry, 
                NULL, NULL, NULL, CONFIG_FS_MGMT_THREAD_PRIORITY, 0, 0);